1. Field of the Invention
The present invention relates to a post-processing apparatus which performs a binding process after collating and stacking, on a processing tray, sheets fed from an image forming apparatus and stores the sheets on a stack tray, and relates to improvement of a sheet conveying mechanism which prevents sheets from being jammed in a binding processing mechanism.
2. Description of Related Arts
In general, such an apparatus is connected to a sheet discharging port of an image forming apparatus. Such an apparatus has been widely known as an apparatus in which a binding process is performed on sheets fed from the sheet discharging port and the processed sheet bundle is stored on a stack tray at the downstream side. As a structure thereof, there has been known a stand-alone structure that the apparatus is connected to a sheet discharging port of an image forming apparatus and a binding process is performed on sheets fed from the sheet discharging port and introduced onto a processing tray and that the sheets are stored on a stack tray at the downstream side. Further, there has been known an inner finisher structure that the apparatus is assembled into a sheet discharging area of an image forming apparatus and sheets fed from a sheet discharging port are collated on a processing tray and a binding process is performed thereon, and then, the sheets are stored on a stack tray.
For example, Japanese Patent Application Laid-open No. 2011-256008 discloses a post-processing apparatus which is connected to an image forming apparatus. Here, image-formed sheets are stacked on a processing tray and first and the second binding processing device are arranged at the processing tray. After one selected binding processing device performs a binding process on sheets, the sheet bundle is discharged to and stored in a stack tray at the downstream side.
Japanese Patent Application Laid-open No. 2011-256008 includes a regulating stopper to perform regulating by abutting a sheet end to the processing tray, an aligning device (side aligning plate) to bias and move a sheet bundle abutted to the regulating stopper in the width direction, and a binding processing device to perform a binding process on the sheet bundle which is positioned by the regulating stopper and the aligning plate. Here, a staple-binding device to perform staple-binding on a side edge of a sheet bundle on the processing tray and a non-staple binding device to perform a non-staple binding are arranged as the binding processing device. Then, a binding process is performed by a single selected device.